Piston



Feb. 7, 1933. J. A. SPEER- 1,896,124

PISTON Filed Jan. 5l, 1931 NVENTOR X4/VES A. Spne B A TTORNEY Patented Feb. 7, 1933 UNITED STATES JAMES A. SPEEB, OF 'WICHITA PrsroN Application alealanuary a1, 193i. Aserial No. 5125,12. y

This invention relates to improvements in an internal combustion engine and particularly to means for cooling the piston, and means for utilizing the piston for cooling the oil in the crank case of the engine. This is a particular advantage in air cooled engines.

By maintaining the inner end of the piston relatively cool and passing kthe air current of the fuel charge through the piston, the relatively cool charge can be compressed to a higher degree thanis possible in an ordinary engine construction, since it is well recognized `that the higher the compression of the fuel charge, prior to combustion, the more eflicient the engine will be. It is obvious that my invention has certain advantages over engines of the ordinary type.

The novelty of my invention will be apparent by referring to the following description in connection with the accompanying drawing in which:

Fig. 1 is a view of a cylinder of a motor, part of which is in elevation and part in section, the piston being shown in section eX- cept for the connecting rod.

Fig. 2 is a cross sectional view through the piston at right angles to the section shown in Fig. 3 is a perspective view of lpart of the piston, parts being broken away to show they cooling fins and the fuel passageway there thru.

Referring now to the drawing by numerals of reference:

1 designates a cylinder of an internal combustion engine of the air cooledftype, having an intake conduit communicating with the carburetor not shown, connected to a pipe 3 secured to the outlet 4 of a passageway 5 in lthe piston 6, the passageway having an inlet sub-passageways as shown, and immediately below the partitions 18 and carried by the inverted V shaped web 17 are similar oil cooling webs 19 which project. intothe `skirt of the piston toward the wrist pin of the u connecting rod. y i

On thesuction stroke of the piston, fuel is drawn through the carburetor into the engine, but the air supply is drawn through the opening 8, throughv opening 7, through the sub-passageways, through opening 4', through opening 4, through pipev 3, through the carburetor and hence to the intake pipe or manifold 2. The cool outside atmosphere will take up some of the heat .from the partitions or fins 18 before it enters the carburetor'to commingle with the hydrocarbon content of the fuel mixture, so that thepiston will ble kept relatively cool. As the piston reciprocates, the oil in the crank case will splashon the fins or web 19, and since they are integral with the V shaped lpartition or web 17 andinline with the webs 18, they will remain relativelycool, thereby keeping the oilcool.` n n y y v i The V shaped web or `partition 17 will slightly choke thepassage-way of the air through the piston -to give it suicient time to dissipate a considerable amount ofv heat 'from the piston. The webs and partitions in the piston, as well as the head and skirt, can allbelcastintegral, so that'the piston may be constructed at a very low cost. Of course, appropriate sealing rings 20 will be pr0- vided for the piston at appropriate places.

Inasmuch as the incoming air passes through the piston and cools it, it will take up some of the heat, this heat being useful in vaporing the liquid fuel in the carburetor. The mixture will not be so hot however, as to its inlet 7 and outlet 4 f f Q interfere with high compression in the engine.

Attention is called to the fact that as the piston registers with the inlet opening 8, a fresh charge of cool air is drawn into the passageway 5. As the piston ports lap the inlet and outlet ports in the cylinder, this cool air is trapped in the passageway, which now becomes a cooling chamber in the piston to maintain the piston at a low temperature during all four strokes of the piston. This n will prevent the piston from becoming exoessively hot, and as heretofore pointed out, the heat taken up by the air will tend to enhance the vaporization of the liquid content ofthe fuel miXure as this relatively warm air passes through the carburetor. Where any forced feed oil system is employed the oil of course will be pumped through the 2c@ par-ts to be lubricated underpressure in the usual way, and this positive feed of the oil will cause the oil to contact With the oil cooling fins so that new oil will constantly flow over `the oil cooling fins and thereby have 2'@ its temperature maintained relatively low.

Of course it is understood-that the engine is susceptible for use with a supercharger, in which event the supercharged air would be forced under pressure into the 3513 inlet 7 instead of depending upon the suction stroke oi the piston for drawing the air through the carburetor.

What I claim and desire -to secure by Letters Patent is i 1. A piston comprising a head having a cylindrical skirt provided with alining openings, an inverted V shaped web spaced from the head to provide a passageway between the openings, and oil cooling fins on the outer 41E face of the web.

2. A piston comprising a head having a cylindical skirt with alining openings, a Web spaced from the head to provide a passageway between the openings, lheat conducting webs connecting the first named web and the head, and ns connected -to the outer face of the web.

3. A piston comprising a head having a cylindrical skirt provided with aligning o enings, an inverted V-shaped web spaced rom the head to provide a passageway between the openings, air-cooling fins connecting the web and head to divide the passageway into a plurality of ducts and oil cooling fins on ghe face of the web opposite to the rst named In testimony whereof I aiix my signature.

1 JAMES A. SPEER. 

